Improvement in millstone-drivers



w. JOHNSON.

- MILLS'IONE-DRIV'ER; No. 190,439. v Patented May 8,1877.

W/T/VESSL'SZ aw: 7 0 v UNITED STATES FFIGE.

WILLIAM JOHNSON, OF MILWAUKEE, WISOON SIN, ASSIGNOR OF ONE-HALF HIS RIGHT TO JOHN KELNER, OF SAME PLACE.

IMPROVEMENT IN MlLLSTONE-DRIVERS.

Specification forming part of Letters Patent No. 190,439, dated May 8, 1877; application filed December 26, 1876.

To all whom it may concern:

Be it known that I, WILLIAM JOHNSON, of Milwaukee, in the county of Milwaukee, in the State of Wisconsin, have invented certain Im tive of the top.

A represents the frame of the driver, which has a suitable hole, Gr, through its center for passing down over the mill-spindle, and the flanges I on opposite sides, to hold the other parts in position. Pivoted upon the top of this frame, between the flanges l, and on opposite sides of the hole G, are the two blocks E, which have the openings F made in their outer projecting edges, so that the blocks will catch over the hail of the stone. These blocks, being pivoted upon projecting pins upon the top of the frame, and not being wide enough to fill the space between the flanges I, can 0s cillate from side to side. Upon the top of each block are formed the shoulders O, and

the space between the shoulders on the blocks and the flanges I on the sides of the frame forms a recess, in'which is placed the link B. Over the top of this link is placed the cover D, so as to keep all the parts in position, and which has a corresponding hole, Gr, through it, to let the spindle pass through.

The operation is as follows: The driver is placed upon the spindle, so as to turn with it; and as the driver turns, it turns the stone with it. As the block E strikes the bail on one side of the stone, the shoulders C of the block push the link B against the shoulders of the block on the other side of the driver, and this block strikes against the bail on that side. In this way both. sides of the driver take up at once and turn the stone steadily, 

